The present invention relates in general to a semiconductor integrated circuit device having a Schottky barrier diode, and more particularly, to a semiconductor integrated circuit device having a plurality of Schottky barrier diodes whose forward voltage is low.
Heretofore, a semiconductor integrated circuit device in which a plurality of Schottky barrier diodes (hereinafter abbreviated as SBD's) are formed on a surface of one conductivity region of a semiconductor substrate, and in which one part of the one conductivity region is connected to one electrode that is common to the SBD's, has been often used in a logic circuit, as is illustrated and described, for example, in IEEE JOURNAL OF SOLID-STATE CIRCUITS, Vol. SC-10, No. 5, October 1975, pp. 343-348. In such a device, when the common electrode has taken a predetermined condition, it is necessary for the plurality of SBD's to operate simultaneously. However, the forward voltage V.sub.F of an SBD provided at a location remote from the electrode becomes higher than that of an SBD near the electrode, so that the simultaneous operation of the SBD's would become impossible. In a semiconductor integrated circuit device, on an insulating film between SBD's are provided wiring layers to be connected to the other parts of the device, so that naturally the distance between the common electrode and the SBD becomes long and the forward voltage V.sub.F of the SBD becomes still greater. As one solution for this problem it may be conceived to provide a high impurity concentration region of one conductivity type in the semiconductor surface between the SBD's where an SBD is not formed, but even with such provision a satisfactory result cannot be expected.